Incident details
Operator, cause, commodity and consequences with raw source fields.
GTG incident on 2014-09-15 — OK
Operator
Transcontinental Gas Pipe Line Company
Cause
Corrosion Failure
Commodity
Natural Gas
Program
GTG
Damage and Injuries
0 fatalities
0 injuries
Property damage (nominal)
$475,000
Incident datetime
2014-09-15 12:10
Report number
Location
OK
Narrative
Williams - transco district manager warren toups was notified by dan mcknight from helis on 9-15-14 at 9:15am that they were investigating some bubbles in the ss 47 area, near where their 4" pipeline crossed over transco's 26" line. Dan stated they first noticed the bubbles about 3:30pm on 9-13-14. The barely visible sheen covered approximately 300 feet wide by 2600 feet long with 50% coverage. They reported the leak & sheen to nrc at 6:10pm, nrc #1095249. Transco was informed that helis had shut-in and blown down their wells. This led them to believe the bubbles were possibly coming from the transco 26" line. Helis also utilized the services of oil mops(osro) to contain the sheen and the services of blackwater divers who had arrived at the location earlier that morning. We (transco) plotted coordinates on our alignment sheets, but it plotted out about 1500 feet from transco 26". Our technicians, were sent out by helicopter to fly over leak site and land at ss 45 platform(helis owned). At 11:35am, our technician called with details of the sheen which was very light and measured 5 miles long and 300 feet wide with about 30% coverage. Our technician relayed to US updated coordinates taken by the helicopter. He took a field boat to leak site and was informed by blackwater divers they suspected that the bubbles were coming from transco 26" line. At 1:35pm, transco schriever office was informed that bubbles were coming from the transco 26" pipeline. Helis called o'briens at 12 noon on 9-15-14 to inform them that the leak did not belong to helis. Schriever office assumed the original nrc #1095249 that helis had called in would also apply to transco leak on the 26" pipeline. After confirming with bud kline and with o'brien's that another nrc # was necessary, toups contacted o'brien's at 3:13pm and williams (transco) gas control at 3:20pm. O'briens contacted nrc at 3:35pm and received nrc #1095398. O'brien's also contacted la. State police at 3:42pm and received #14-04128. Schriever district personnel isolated the 26" pipeline segment 5103 at ship shoal 70 platform and at dog lake generator platform at 4:22pm. Negotiations continued between transco & helis to utilize the osro (oil mops) and blackwater divers as well as the lift boat on location the divers were using. Transco was able to utilize oil mops personnel and equipment, but not blackwater divers and lift boat. Schriever then requested oil mops personnel to use absorbent boom to encircle the bubbles, capturing any sheening within the boom. A dive vessel that was being used by transco on another job, was requested to relocate to leak location as soon as possible. Inclement weather caused some delays with the pipeline blowdown and the repair. Summary of leak investigation & repair of the leak: divers were sent down to the leaking pipe, they performed a ut scan on all sides of the leaking pipe and verified that the the leak was not external. The leak occurred on the low point of the pipe, near the 6 o'clock position. A clamp was used to repair the leak and the line was gradually pressured back up to maop on 9-29-2014 at 3:15 pm; no leaks were detected. The history of this gathering pipeline system has been the transportation of unprocessed undehydrated natural gas since 1990. Transco follows has a strict internal corrosion monitoring and control policy, this line has been treated since 1990 with corrosion inhibitors and biocides. Samples are collected and residuals are monitored monthly. Field technicians measure chemical quantities and chemical injection pump operations monthly. Internal corrosion leak documentation is provided to asset integrity internal corrosion engineers for recommendations.
Detailed record list
Report Received Date
2014-10-13 00:00:00
Iyear
2014
Report Number
20140105
Supplemental Number
16566
Report Type
Supplemental Final
Operator Id
19570
Name
Transcontinental Gas Pipe Line Company
Operator Street Address
One Williams Center Md 43-4
Operator City Name
Tulsa
Operator State Abbreviation
OK
Operator Postal Code
74172
Local Datetime
2014-09-15 12:00:00
Location Latitude
29.017667
Location Longitude
-90.898028
Nrc Rpt Num
1095398
Nrc Rpt Datetime
2014-09-15 15:35:00
Commodity Released Type
Natural Gas
Unintentional Release
0.1
Intentional Release
14000
Accompanying Liquid
0
Fatality Ind
No
Fatal
0
Injury Ind
No
Injure
0
Shutdown Due Accident Ind
Yes
Shutdown Datetime
2014-09-15 16:22:00
Restart Datetime
2014-09-29 16:03:00
Ignite Ind
No
Explode Ind
No
Num Pub Evacuated
0
Incident Identified Datetime
2014-09-15 12:10:00
On Site Datetime
2014-09-15 12:10:00
On Off Shore
Offshore
Off Water Depth
20
Off Accident Origin
In State Waters
Offshore State Abbreviation
La
Off Instate Area
Ship Shoal
Off Instate Block
Ss47/state Lease 147922
Offshore County Name
Terrebonne
Off Area Accident Type
Below Water, Pipe Buried Or Jetted Below Seabed
Pipe Facility Type
Interstate
System Part Involved
Offshore Pipeline, Including Riser And Riser Bend
Item Involved
Weld/fusion, Including Heat-Affected Zone
Pipe Diameter
26
Pipe Wall Thickness
0.5
Pipe Smys
52000
Pipe Specification
Api 5l
Pipe Seam Type
Longitudinal Erw - High Frequency
Pipe Manufacturer
U.s. Steel Corp
Pipe Coating Type
Other
Pipe Coating Details
External Coating Type - Asphalt With 3 Inch Of Concrete.
Weld Subtype
Pipe Girth Weld
Installation Year
1969
Manufactured Year
1969
Material Involved
Carbon Steel
Release Type
Leak
Leak Type
Pinhole
Class Location Type
Class 1 Location
Could Be Hca
No
Pir Radius
474
Heat Damage Ind
No
Non Heat Damage Ind
No
Hca Fatalities Ind
No
Est Cost Oper Paid
0
Est Cost Unintentional Release
404
Est Cost Intentional Release
56546
Est Cost Prop Damage
475000
Est Cost Emergency
75000
Est Cost Other
0
Prpty
606950
Accident Psig
697
Mop Psig
1440
Mop Cfr Section
Not On Omb-Approved Form When Submitted
Accident Pressure
Pressure Did Not Exceed Maop
Pressure Restriction Ind
No
Upstream Valve Type Ind
Manual
Downstream Valve Type Ind
Manual
Length Segment Isolated
91661
Internal Inspection Ind
No
Other Inspection Ind
Yes
Internal Inspection Details
Pig Traps Were Not Designed To Accommodate Internal Inspection Tools.
Operation Complications Ind
Yes
Low Flow Ind
Yes
Other Complications Ind
Yes
Inspect Comp Details
Pipline Design.
Pipeline Function
Offshore Gathering
Scada In Place Ind
Yes
Scada Operating Ind
Yes
Scada Functional Ind
Yes
Scada Detection Ind
No
Scada Conf Ind
No
Accident Identifier
Other
Accident Details
By Other Producer Employees Working Near The Leak Location.
Investigation Status
No, the operator did not find that an investigation of the controller(s) actions or control room issues was necessary due to: (provide an explanation for why the operator did not investigate)
Investigation Status Details
Leak was very small, minimal pressure change, therefore controllers would not have detected leak.
Employee Drug Test Ind
No
Contractor Drug Test Ind
No
Cause
Corrosion Failure
Cause Details
Internal Corrosion
Internal External
Internal Corrosion
Int Visual Exam Results
Not Cut Open
Int Other Corrosion Ind
Yes
Int Corrosion Type Details
This Pipeline Transports Unprocessed Undehydrated Gas, Since 1990.
Int Field Exam Basis Ind
Yes
Int Other Basis Ind
Yes
Int Corrosion Basis Details
Ut Inspection By Divers Resulted In No External Corrosion.
Int Low Point Pipe Loc Ind
Yes
Corrosion Inhibitors
Yes
Corrosion Lining
No
Cleaning Dewatering
Yes
Corrosion Coupons
Yes
Collected Data Ind
No
Has Hydrtst Conduc Before Ind
No
Direct Asmnt Conducted
No
Non Destructive Exam Ind
No
Preparer Name
J***** L****
Preparer Title
Regulatory Compliance Specialist
Preparer Email
J***********@w*******.com
Preparer Telephone
7132152995
Preparer Fax
713-215-2222
Authorizer Name
M**** S****
Authorizer Title
Manager Pipeline And Process Safety
Authorizer Telephone
7132152111
Authorizer Email
M**********@w*******.com
Narrative
Williams - transco district manager warren toups was notified by dan mcknight from helis on 9-15-14 at 9:15am that they were investigating some bubbles in the ss 47 area, near where their 4" pipeline crossed over transco's 26" line. Dan stated they first noticed the bubbles about 3:30pm on 9-13-14. The barely visible sheen covered approximately 300 feet wide by 2600 feet long with 50% coverage. They reported the leak & sheen to nrc at 6:10pm, nrc #1095249. Transco was informed that helis had shut-in and blown down their wells. This led them to believe the bubbles were possibly coming from the transco 26" line. Helis also utilized the services of oil mops(osro) to contain the sheen and the services of blackwater divers who had arrived at the location earlier that morning. We (transco) plotted coordinates on our alignment sheets, but it plotted out about 1500 feet from transco 26". Our technicians, were sent out by helicopter to fly over leak site and land at ss 45 platform(helis owned). At 11:35am, our technician called with details of the sheen which was very light and measured 5 miles long and 300 feet wide with about 30% coverage. Our technician relayed to US updated coordinates taken by the helicopter. He took a field boat to leak site and was informed by blackwater divers they suspected that the bubbles were coming from transco 26" line. At 1:35pm, transco schriever office was informed that bubbles were coming from the transco 26" pipeline. Helis called o'briens at 12 noon on 9-15-14 to inform them that the leak did not belong to helis. Schriever office assumed the original nrc #1095249 that helis had called in would also apply to transco leak on the 26" pipeline. After confirming with bud kline and with o'brien's that another nrc # was necessary, toups contacted o'brien's at 3:13pm and williams (transco) gas control at 3:20pm. O'briens contacted nrc at 3:35pm and received nrc #1095398. O'brien's also contacted la. State police at 3:42pm and received #14-04128. Schriever district personnel isolated the 26" pipeline segment 5103 at ship shoal 70 platform and at dog lake generator platform at 4:22pm. Negotiations continued between transco & helis to utilize the osro (oil mops) and blackwater divers as well as the lift boat on location the divers were using. Transco was able to utilize oil mops personnel and equipment, but not blackwater divers and lift boat. Schriever then requested oil mops personnel to use absorbent boom to encircle the bubbles, capturing any sheening within the boom. A dive vessel that was being used by transco on another job, was requested to relocate to leak location as soon as possible. Inclement weather caused some delays with the pipeline blowdown and the repair. Summary of leak investigation & repair of the leak: divers were sent down to the leaking pipe, they performed a ut scan on all sides of the leaking pipe and verified that the the leak was not external. The leak occurred on the low point of the pipe, near the 6 o'clock position. A clamp was used to repair the leak and the line was gradually pressured back up to maop on 9-29-2014 at 3:15 pm; no leaks were detected. The history of this gathering pipeline system has been the transportation of unprocessed undehydrated natural gas since 1990. Transco follows has a strict internal corrosion monitoring and control policy, this line has been treated since 1990 with corrosion inhibitors and biocides. Samples are collected and residuals are monitored monthly. Field technicians measure chemical quantities and chemical injection pump operations monthly. Internal corrosion leak documentation is provided to asset integrity internal corrosion engineers for recommendations.
| Report Received Date | 2014-10-13 00:00:00 |
|---|---|
| Iyear | 2014 |
| Report Number | 20140105 |
| Supplemental Number | 16566 |
| Report Type | Supplemental Final |
| Operator Id | 19570 PHMSA Enforcement |
| Name | Transcontinental Gas Pipe Line Company |
| Operator Street Address | One Williams Center Md 43-4 |
| Operator City Name | Tulsa |
| Operator State Abbreviation | OK |
| Operator Postal Code | 74172 |
| Local Datetime | 2014-09-15 12:00:00 |
| Location Latitude | 29.017667 Google Maps OpenStreetMap |
| Location Longitude | -90.898028 Google Maps OpenStreetMap |
| Nrc Rpt Num | 1095398 NRC Report How to search |
| Nrc Rpt Datetime | 2014-09-15 15:35:00 |
| Commodity Released Type | Natural Gas |
| Unintentional Release | 0.1 |
| Intentional Release | 14000 |
| Accompanying Liquid | 0 |
| Fatality Ind | No |
| Fatal | 0 |
| Injury Ind | No |
| Injure | 0 |
| Shutdown Due Accident Ind | Yes |
| Shutdown Datetime | 2014-09-15 16:22:00 |
| Restart Datetime | 2014-09-29 16:03:00 |
| Ignite Ind | No |
| Explode Ind | No |
| Num Pub Evacuated | 0 |
| Incident Identified Datetime | 2014-09-15 12:10:00 |
| On Site Datetime | 2014-09-15 12:10:00 |
| On Off Shore | Offshore |
| Off Water Depth | 20 |
| Off Accident Origin | In State Waters |
| Offshore State Abbreviation | La |
| Off Instate Area | Ship Shoal |
| Off Instate Block | Ss47/state Lease 147922 |
| Offshore County Name | Terrebonne |
| Off Area Accident Type | Below Water, Pipe Buried Or Jetted Below Seabed |
| Pipe Facility Type | Interstate |
| System Part Involved | Offshore Pipeline, Including Riser And Riser Bend |
| Item Involved | Weld/fusion, Including Heat-Affected Zone |
| Pipe Diameter | 26 |
| Pipe Wall Thickness | 0.5 |
| Pipe Smys | 52000 |
| Pipe Specification | Api 5l |
| Pipe Seam Type | Longitudinal Erw - High Frequency |
| Pipe Manufacturer | U.s. Steel Corp |
| Pipe Coating Type | Other |
| Pipe Coating Details | External Coating Type - Asphalt With 3 Inch Of Concrete. |
| Weld Subtype | Pipe Girth Weld |
| Installation Year | 1969 |
| Manufactured Year | 1969 |
| Material Involved | Carbon Steel |
| Release Type | Leak |
| Leak Type | Pinhole |
| Class Location Type | Class 1 Location |
| Could Be Hca | No |
| Pir Radius | 474 |
| Heat Damage Ind | No |
| Non Heat Damage Ind | No |
| Hca Fatalities Ind | No |
| Est Cost Oper Paid | 0 |
| Est Cost Unintentional Release | 404 |
| Est Cost Intentional Release | 56546 |
| Est Cost Prop Damage | 475000 |
| Est Cost Emergency | 75000 |
| Est Cost Other | 0 |
| Prpty | 606950 |
| Accident Psig | 697 |
| Mop Psig | 1440 |
| Mop Cfr Section | Not On Omb-Approved Form When Submitted View CFR 49 §192 |
| Accident Pressure | Pressure Did Not Exceed Maop |
| Pressure Restriction Ind | No |
| Upstream Valve Type Ind | Manual |
| Downstream Valve Type Ind | Manual |
| Length Segment Isolated | 91661 |
| Internal Inspection Ind | No |
| Other Inspection Ind | Yes |
| Internal Inspection Details | Pig Traps Were Not Designed To Accommodate Internal Inspection Tools. |
| Operation Complications Ind | Yes |
| Low Flow Ind | Yes |
| Other Complications Ind | Yes |
| Inspect Comp Details | Pipline Design. |
| Pipeline Function | Offshore Gathering |
| Scada In Place Ind | Yes |
| Scada Operating Ind | Yes |
| Scada Functional Ind | Yes |
| Scada Detection Ind | No |
| Scada Conf Ind | No |
| Accident Identifier | Other |
| Accident Details | By Other Producer Employees Working Near The Leak Location. |
| Investigation Status | No, the operator did not find that an investigation of the controller(s) actions or control room issues was necessary due to: (provide an explanation for why the operator did not investigate) |
| Investigation Status Details | Leak was very small, minimal pressure change, therefore controllers would not have detected leak. |
| Employee Drug Test Ind | No |
| Contractor Drug Test Ind | No |
| Cause | Corrosion Failure |
| Cause Details | Internal Corrosion |
| Internal External | Internal Corrosion |
| Int Visual Exam Results | Not Cut Open |
| Int Other Corrosion Ind | Yes |
| Int Corrosion Type Details | This Pipeline Transports Unprocessed Undehydrated Gas, Since 1990. |
| Int Field Exam Basis Ind | Yes |
| Int Other Basis Ind | Yes |
| Int Corrosion Basis Details | Ut Inspection By Divers Resulted In No External Corrosion. |
| Int Low Point Pipe Loc Ind | Yes |
| Corrosion Inhibitors | Yes |
| Corrosion Lining | No |
| Cleaning Dewatering | Yes |
| Corrosion Coupons | Yes |
| Collected Data Ind | No |
| Has Hydrtst Conduc Before Ind | No |
| Direct Asmnt Conducted | No |
| Non Destructive Exam Ind | No |
| Preparer Name | J***** L**** |
| Preparer Title | Regulatory Compliance Specialist |
| Preparer Email | J***********@w*******.com |
| Preparer Telephone | 7132152995 |
| Preparer Fax | 713-215-2222 |
| Authorizer Name | M**** S**** |
| Authorizer Title | Manager Pipeline And Process Safety |
| Authorizer Telephone | 7132152111 |
| Authorizer Email | M**********@w*******.com |
| Narrative | Williams - transco district manager warren toups was notified by dan mcknight from helis on 9-15-14 at 9:15am that they were investigating some bubbles in the ss 47 area, near where their 4" pipeline crossed over transco's 26" line. Dan stated they first noticed the bubbles about 3:30pm on 9-13-14. The barely visible sheen covered approximately 300 feet wide by 2600 feet long with 50% coverage. They reported the leak & sheen to nrc at 6:10pm, nrc #1095249. Transco was informed that helis had shut-in and blown down their wells. This led them to believe the bubbles were possibly coming from the transco 26" line. Helis also utilized the services of oil mops(osro) to contain the sheen and the services of blackwater divers who had arrived at the location earlier that morning. We (transco) plotted coordinates on our alignment sheets, but it plotted out about 1500 feet from transco 26". Our technicians, were sent out by helicopter to fly over leak site and land at ss 45 platform(helis owned). At 11:35am, our technician called with details of the sheen which was very light and measured 5 miles long and 300 feet wide with about 30% coverage. Our technician relayed to US updated coordinates taken by the helicopter. He took a field boat to leak site and was informed by blackwater divers they suspected that the bubbles were coming from transco 26" line. At 1:35pm, transco schriever office was informed that bubbles were coming from the transco 26" pipeline. Helis called o'briens at 12 noon on 9-15-14 to inform them that the leak did not belong to helis. Schriever office assumed the original nrc #1095249 that helis had called in would also apply to transco leak on the 26" pipeline. After confirming with bud kline and with o'brien's that another nrc # was necessary, toups contacted o'brien's at 3:13pm and williams (transco) gas control at 3:20pm. O'briens contacted nrc at 3:35pm and received nrc #1095398. O'brien's also contacted la. State police at 3:42pm and received #14-04128. Schriever district personnel isolated the 26" pipeline segment 5103 at ship shoal 70 platform and at dog lake generator platform at 4:22pm. Negotiations continued between transco & helis to utilize the osro (oil mops) and blackwater divers as well as the lift boat on location the divers were using. Transco was able to utilize oil mops personnel and equipment, but not blackwater divers and lift boat. Schriever then requested oil mops personnel to use absorbent boom to encircle the bubbles, capturing any sheening within the boom. A dive vessel that was being used by transco on another job, was requested to relocate to leak location as soon as possible. Inclement weather caused some delays with the pipeline blowdown and the repair. Summary of leak investigation & repair of the leak: divers were sent down to the leaking pipe, they performed a ut scan on all sides of the leaking pipe and verified that the the leak was not external. The leak occurred on the low point of the pipe, near the 6 o'clock position. A clamp was used to repair the leak and the line was gradually pressured back up to maop on 9-29-2014 at 3:15 pm; no leaks were detected. The history of this gathering pipeline system has been the transportation of unprocessed undehydrated natural gas since 1990. Transco follows has a strict internal corrosion monitoring and control policy, this line has been treated since 1990 with corrosion inhibitors and biocides. Samples are collected and residuals are monitored monthly. Field technicians measure chemical quantities and chemical injection pump operations monthly. Internal corrosion leak documentation is provided to asset integrity internal corrosion engineers for recommendations. |
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